Development of immuno-monitoring methods and immunotherapy using glioma antigens

本研究通过对胶质瘤患者血清进行SEREX（重组表达克隆抗原的血清学鉴定）筛选人类睾丸cDNA文库，鉴定出胶质瘤抗原SOX6，一个与sry相关的HMG（高迁移率组）box-containing基因。36例胶质瘤患者中有12例（33.3%），14例其他脑部疾病患者中有0例（0%），54例其他癌症患者中有1例（1.9%）血清中检测到SOX6 IgG抗体。在37名健康人的血清中，除1名老年女性外，未检测到针对SOX6的IgG应答。此外，对胶质瘤患者血清的Western blot和ELISA分析显示，SOX6的dna结合结构域HMG盒可能是抗SOX6的igg的显性表位。RT-PCR和Northern blot分析显示，除了睾丸外，SOX6基因在胶质瘤组织中的表达高于正常成人组织。抗SOX6抗体免疫组化分析显示，所分析的胶质瘤组织在肿瘤细胞中均表达SOX6，而在大脑皮层非肿瘤组织中仅检测到少量SOX6阳性细胞。通过t细胞表位分析，我们鉴定了两个源自SOX6抗原的HLA-A24限制性肽。使用这些表位肽，我们证明可以诱导针对胶质瘤抗原SOX6的细胞毒性T细胞。综上所述，我们鉴定了一种胶质瘤抗原SOX6，并分析了SOX6的表达模式、抗原特异性和T细胞表位。

In this study, a human testis cDNA library was screened by SEREX (serological identification of antigens by recombinant expression cloning) with sera from glioma patients, we identified a glioma antigen, SOX6, an Sry-related HMG (high mobility group) box-containing gene. IgG antibodies against SOX6 were detected in sera from 12 of 36 glioma patients (33.3%), 0 of 14 patients with other brain disease (0%), and 1 of 54 other cancer patients (1.9%). In sera from 37 healthy individuals, no IgG responses against SOX6 were detected, except in an elderly female. Furthermore, Western blot and ELISA analyses with sera from glioma patients revealed that the DNA-binding domain, the HMG box of SOX6, might be a dominant epitope of IgGs against SOX6. RT-PCR and Northern blot analysis revealed that the SOX6 gene was more highly expressed in glioma tissues than in normal adult tissues, except testis. Immunohistochemical analysis with the anti-SOX6 antibody showed that all the glioma tissues analyzed expressed SOX6 in tumor cells, but only a few SOX6-positive cells were detected in nonneoplastic tissues from the cerebral cortex. By T-cell epitope analysis, we idendified two HLA-A24 restricted peptides derived from SOX6 antigen. Using these epitope peptides, we demonstrated to induce cytotoxic T cells specific for the glioma antigen, SOX6. In summary, we identified a glioma antigen, SOX6, and analyzed the expression pattern, antigen specificity, and T cell epitope of the SOX6.